/*
 * Copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * 
 * - Redistribution of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * 
 * - Redistribution in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * 
 * Neither the name of Sun Microsystems, Inc. or the names of
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 * 
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
 * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
 * MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR
 * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR
 * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
 * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
 * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF
 * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 * 
 * You acknowledge that this software is not designed or intended for use
 * in the design, construction, operation or maintenance of any nuclear
 * facility.
 * 
 * Sun gratefully acknowledges that this software was originally authored
 * and developed by Kenneth Bradley Russell and Christopher John Kline.
 */

package uniandes.mundo;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.StreamTokenizer;

import javax.media.opengl.GL;

public class Bunny 
{
	/**
	 * Genera una lista de vista para el modelo bunny
	 */
	public static int gen3DObjectList(GL gl) throws IOException {
		StreamTokenizer tok = new StreamTokenizer(new BufferedReader(
				new InputStreamReader(Bunny.class.getClassLoader()
						.getResourceAsStream("modelos/bunny.txt"))));
		// Reset tokenizer's syntax so numbers are not parsed
		tok.resetSyntax();
		tok.wordChars('a', 'z');
		tok.wordChars('A', 'Z');
		tok.wordChars('0', '9');
		tok.wordChars('-', '-');
		tok.wordChars('.', '.');
		tok.wordChars(128 + 32, 255);
		tok.whitespaceChars(0, ' ');
		tok.whitespaceChars(',', ',');
		tok.whitespaceChars('{', '{');
		tok.whitespaceChars('}', '}');
		tok.commentChar('/');
		tok.quoteChar('"');
		tok.quoteChar('\'');
		tok.slashSlashComments(true);
		tok.slashStarComments(true);

		// Read in file
		int numFaceIndices = nextInt(tok, "number of face indices");
		short[] faceIndices = new short[numFaceIndices * 6];
		for (int i = 0; i < numFaceIndices * 6; i++) {
			faceIndices[i] = (short) nextInt(tok, "face index");
		}
		int numVertices = nextInt(tok, "number of vertices");
		float[] vertices = new float[numVertices * 3];
		for (int i = 0; i < numVertices * 3; i++) {
			vertices[i] = nextFloat(tok, "vertex");
		}
		int numNormals = nextInt(tok, "number of normals");
		float[] normals = new float[numNormals * 3];
		for (int i = 0; i < numNormals * 3; i++) {
			normals[i] = nextFloat(tok, "normal");
		}

		int lid = gl.glGenLists(1);
		gl.glNewList(lid, GL.GL_COMPILE);

		gl.glBegin(GL.GL_TRIANGLES);
		for (int i = 0; i < faceIndices.length; i += 6) {
			for (int j = 0; j < 3; j++) {
				int vi = faceIndices[i + j];
				int ni = faceIndices[i + j + 3];
				gl.glNormal3f(normals[3 * ni], normals[3 * ni + 1],
						normals[3 * ni + 2]);
				gl.glVertex3f(vertices[3 * vi], vertices[3 * vi + 1],
						vertices[3 * vi + 2]);
			}
		}
		gl.glEnd();

		gl.glEndList();
		return lid;
	}

	private static int nextInt(StreamTokenizer tok, String error)
			throws IOException {
		if (tok.nextToken() != StreamTokenizer.TT_WORD) {
			throw new IOException("Parse error reading " + error + " at line "
					+ tok.lineno());
		}
		try {
			return Integer.parseInt(tok.sval);
		} catch (NumberFormatException e) {
			throw new IOException("Parse error reading " + error + " at line "
					+ tok.lineno());
		}
	}

	private static float nextFloat(StreamTokenizer tok, String error)
			throws IOException {
		if (tok.nextToken() != StreamTokenizer.TT_WORD) {
			throw new IOException("Parse error reading " + error + " at line "
					+ tok.lineno());
		}
		try {
			return Float.parseFloat(tok.sval);
		} catch (NumberFormatException e) {
			throw new IOException("Parse error reading " + error + " at line "
					+ tok.lineno());
		}
	}
}
